Apparatus for preparing and softening wood for bending.



W. E. CURRY. APPARATUS FOR PREPARING AND SOFTBNING WOOD FOR BENDING.

APPLICATION FILED JUNE 10, 1908. Y

Patented May 9, 1911.

2 SHEETS-SHEET l.

v I U a? f f 1.

mEQl/y NORRIS PEI-5R1 c0-. wAsI-umzmu, A, c

W. B. CURRY.- APPARATUS] FOR PREPARINGAND SOFTENING WOOD FOR BENDING.

APPLIOATION FILED JUNE 10, 1008. 992, 1 14.

' Patented May 9, 1911.

2 BHEETS-SHEET'2.

3 wuawtoz sra'rns ATENT OFFICE.

APPARATUS FOR PREPARING AND SOFTENING WOOD FOR BENDING.

To all whom it may concern:

Be itknown that I, VILLIAM E. CURRY, a citizen of the United States of America, residing at Parkersburg, in the county of Wood and State of WVest Virginia, have invented new and useful Improvements in Apparatus for Preparing and Softening Wood for Bending, of which the following is a specification.

This invention relates to new and useful improvements in an apparatus for the prep aration and softening of wood for bending purposes whereby the wood to be treated may be subjected to a definite pressure under control, for a given length of time, according to the density and viscosity of the wood to be treated and the retort cleared of all condensation and steam before removing the cover and, the apparatus embodying the improvements, is illustrated in the several views in the accompanying drawings in which like numerals represent correspond ing parts in all the figures.

Figure 1 is a central longitudinal sectional view of my apparatus, the cover being illustrated in its open position by the dotted lines. Fig. 2 is a front elevation, the cover being swung open. Fig. 3 is a sectional view upon the line 33 of Fig. 2. Fig. 4 is a view illustrating the means employed to limit the movement of the yoke when the cover is swung open.

Referring to the drawings, 1 designates a retort of any desired shape provided with the supporting means 2 and 3, suitable means for conveniently closing the retort is provided by means of the cover 22, supported on the thrust screw 19 carried by the yoke 12, which is swingingly mounted on the projections or trunnions 11 secured to opposite sides of the retort 1 and is provided with adjustable counter balancing weights 15. The cover 22 is provided with a packing or washer 23 and is adapted to be forced into steam tight contact with the circular collar 10, made preferably of a non-corrosive metal, by means of the thrust screw 19 and the hand wheel 20.

The pipe 5 is provided to admit steam and is fitted with two valves 5 and 5 5 being a pressure regulating valve capable of being set and to automatically maintain the steam pressure within the retort at any desired point below that in the boiler or source of Specification of Letters Patent.

AppIication filed June 10, 1908.

steam supply.

Leading from the lowermost point of the Patented May 9, 1911.

Serial No. 437,740.

interior of the retort where the condensed steam will accumulate by gravity, an outlet pipe 8, fitted with a valve 9, is provided to permit the condensation to be blown out by the retained pressure after the steam is shut off. A suitable gage 6 is provided to indicate the pressure within the retort, and a safety valve 6, which may be of any convenient type, is also provided against possible failure of the pressure regulating valve to operate at the pressure to which it may be set. Suitable lugs 29, arranged on diametrically opposite sides of the cover, are provided to limit the movement and to maintain the yoke in a substantially vertical position when the cover is swung open.

In operation, the wood to be treated is placed within the retort and may be of sufficient quantity or bulk to substantially fill it. The retort is then made steam and air tight by closing the valve 9 and placing in proper position the cover 22. Steam is then admitted at the required pressure and kept under control by means of the automatic pressure regulating valve 5. Owing to the different degrees of dryness and the great varieties of wood used for bending 'pur poses, and the different steam pressures required to obtain satisfactory results, the steam pressure regulating valve 5 performs an important function, the pressure within the retort being determined and controlled according to the nature, viscosity and hygro scopic condition of the wood under treatment, a pressure of from 20 to 30 lbs. being employed for partly air dried or thoroughly green stock, and a maximum pressure of from 30 to 50 lbs. for thoroughly air dried stock. Having the required pressure, the length of time the steaming process may continue also depends: first upon the viscosity; second, the hygroscopicity; and third, the cross sectional area of the units under treatment. When the wood has been subjected to the required pressure for a sufficient length of time, the inlet valve 5 is closed and the corresponding valve 9, in the discharge pipe opened, the steam remaining within the retort passing out, carrying with it all the condensation, leaving the interior of the retort dry and free from all corrosive influences and the wood so treated free from stain and discoloration. The retort is then opened and the wood removed, when the operation may again be repeated.

Having described my invention, what I Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

upon the trunnions, counter balancing Weights upon the yoke, a threaded collar upon the yoke, a'threaded member engaging 15 WILLIAM E. CURRY.

Witnesses W. C. RILEY, W. E. MODOUGLE.

Washington, D. G. 

